Transition piece, combustor provided with same, and gas turbine provided with combustor

Abstract

A plurality of cooling passages extending in an axial direction are formed in a transition piece so as to be aligned in a circumferential direction and the axial direction. One or more downstream side passages are formed in a downstream side region (Rd) within one circumferential region. One or more upstream side passages are formed in an upstream side region Ru within the circumferential region. The total cross-sectional area per unit circumferential length of the one or more downstream side passages is larger than the total cross-sectional area per unit circumferential length of the one or more upstream side passages.

1 - 20 . (canceled) 
     
     
         21 . A transition piece demarcating a periphery of a combustion gas flow path where combustion gas flows from an upstream side to a downstream side in an axial direction in which an axis extends, wherein:
 a plurality of cooling passages which extend in the axial direction and inside which a cooling medium flows are formed so as to be aligned in the axial direction and a circumferential direction with regard to the axis;   one or more downstream side passages which are a portion of the plurality of cooling passages are formed in a downstream side region on the downstream side within at least one circumferential region in the circumferential direction, and one or more upstream side passages which are another portion of the plurality of cooling passages are formed in an upstream side region on the upstream side with regard to the downstream side region within the circumferential region;   a total cross-sectional area per unit circumferential length of the one or more downstream side passages in the downstream side region is greater than a total cross-sectional area per unit circumferential length of the one or more upstream side passages in the upstream side region; and   a cross-sectional area of the downstream side passage is larger than a cross-sectional area of the upstream side passage.   
     
     
         22 . A transition piece demarcating a periphery of a combustion gas flow path where combustion gas flows from an upstream side to a downstream side in an axial direction in which an axis extends, wherein:
 a plurality of cooling passages which extend in the axial direction and inside which a cooling medium flows are formed so as to be aligned in the axial direction and a circumferential direction with regard to the axis;   one or more downstream side passages which are a portion of the plurality of cooling passages are formed in a downstream side region on the downstream side within at least one circumferential region in the circumferential direction, and one or more upstream side passages which are another portion of the plurality of cooling passages are formed in an upstream side region on the upstream side with regard to the downstream side region within the circumferential region;   a total cross-sectional area per unit circumferential length of the one or more downstream side passages in the downstream side region is greater than a total cross-sectional area per unit circumferential length of the one or more upstream side passages in the upstream side region; and   an inlet is formed at a first end portion of the plurality of cooling passages, and an outlet is formed at a second end portion of the plurality of cooling passages.   
     
     
         23 . The transition piece according to  21 , wherein the number of the downstream side passages in the downstream side region is higher than the number of the upstream side passages in the upstream side region. 
     
     
         24 . A transition piece demarcating a periphery of a combustion gas flow path where combustion gas flows from an upstream side to a downstream side in an axial direction in which an axis extends, wherein:
 a plurality of cooling passages which extend in the axial direction and inside which a cooling medium flows are formed so as to be aligned in the axial direction and a circumferential direction with regard to the axis;   one or more downstream side passages which are a portion of the plurality of cooling passages are formed in a downstream side region on the downstream side within at least one circumferential region in the circumferential direction, and one or more upstream side passages which are another portion of the plurality of cooling passages are formed in an upstream side region on the upstream side with regard to the downstream side region within the circumferential region; and   a ratio of a cross-sectional area of the downstream side passage to a length in the axial direction of the downstream side passage is larger than a ratio of a cross-sectional area of the upstream side passage to a length in the axial direction of the upstream side passage.   
     
     
         25 . The transition piece according to  claim 24 , wherein the length in the axial direction of the downstream side passage is shorter than the length in the axial direction of the upstream side passage. 
     
     
         26 . The transition piece according to  claim 22 , wherein a cross-sectional area of the downstream side passage is larger than a cross-sectional area of the upstream side passage. 
     
     
         27 . The transition piece according to  claim 21 , comprising a body portion that demarcates a portion of the combustion gas flow path, is formed by bonding ends of one or more plate materials together, and has a bonded portion that is a portion where the ends of the one or more plate materials are bonded together and extends in the axial direction, wherein the upstream side passage and the downstream side passage are formed in the body portion. 
     
     
         28 . The transition piece according to  claim 21 , provided in a gas turbine casing that covers a gas turbine rotor, wherein:
 one or more rotor side passages which are a portion of the plurality of cooling passages are formed in a rotor side region opposing the gas turbine rotor in at least one axial region in the axial direction, and one or more casing side passages which are another portion of the plurality of cooling passages are formed in a casing side region opposing an inner circumferential surface of the gas turbine casing within the axial region; and   a total cross-sectional area per unit circumferential length of the one or more casing side passages in the casing side region is larger than a total cross-sectional area per unit circumferential length of the one or more rotor side passages in the rotor side region.   
     
     
         29 . A transition piece provided in a gas turbine casing that covers a gas turbine rotor and demarcating a periphery of a combustion gas flow path where combustion gas flows from an upstream side to a downstream side in an axial direction in which an axis extends, wherein:
 a plurality of cooling passages which extend in the axial direction and inside which a cooling medium flows are formed so as to be aligned in a circumferential direction with regard to the axis;   one or more rotor side passages which are a portion of the plurality of cooling passages are formed in a rotor side region opposing the gas turbine rotor within at least one axial region in the axial direction, and one or more casing side passages which are another portion of the plurality of cooling passages are formed in a casing side region opposing an inner circumferential surface of the gas turbine casing within the axial region; and   a total cross-sectional area per unit circumferential length of the one or more casing side passages in the casing side region is greater than a total cross-sectional area per unit circumferential length of the one or more rotor side passages in the rotor side region.   
     
     
         30 . The transition piece according to  claim 28 , wherein the number of the casing side passages in the casing side region is higher than the number of the rotor side passages in the rotor side region. 
     
     
         31 . A transition piece provided in a gas turbine casing that covers a gas turbine rotor and demarcating a periphery of a combustion gas flow path where combustion gas flows from an upstream side to a downstream side in an axial direction in which an axis extends, wherein:
 a plurality of cooling passages which extend in the axial direction and inside which a cooling medium flows are formed so as to be aligned in a circumferential direction with regard to the axis;   one or more rotor side passages which are a portion of the plurality of cooling passages are formed in a rotor side region opposing the gas turbine rotor within at least one axial region in the axial direction, and one or more casing side passages which are another portion of the plurality of cooling passages are formed in a casing side region opposing an inner circumferential surface of the gas turbine casing within the axial region; and   a ratio of a cross-sectional area of the casing side passage to a length in the axial direction of the casing side passage is larger than a ratio of a cross-sectional area of the rotor side passage to a length in the axial direction of the rotor side passage.   
     
     
         32 . The transition piece according to  claim 31 , wherein the length in the axial direction of the casing side passage is shorter than the length in the axial direction of the rotor side passage. 
     
     
         33 . The transition piece according to  claim 28 , wherein the cross-sectional area of the casing side passage is larger than the cross-sectional area of the rotor side passage. 
     
     
         34 . The transition piece according to  claim 28 , comprising a body portion that demarcates a portion of the combustion gas flow path, is formed by bonding ends of one or more plate materials together, and has a bonded portion that is a portion where the ends of the one or more plate materials are bonded together and extends in the axial direction, wherein the casing side passage and the rotor side passage are formed in the body portion. 
     
     
         35 . The transition piece according to  claim 27 , wherein a length in the axial direction of a bond side passage of the plurality of cooling passages that is nearest to the bonded portion in the circumferential direction is shorter than a length in the axial direction of an adjacent passage of the plurality of cooling passages that is adjacent to the bond side passage in the circumferential direction. 
     
     
         36 . A transition piece demarcating a periphery of a combustion gas flow path where combustion gas flows from an upstream side to a downstream side in an axial direction in which an axis extends, comprising a body portion that demarcates a portion of the combustion gas flow path, is formed by bonding ends of one or more plate materials together, and has a bonded portion that is a portion where the ends of the one or more plate materials are bonded together and extends in the axial direction, wherein:
 a plurality of cooling passages which extend in the axial direction and inside which a cooling medium flows are formed so as to be aligned in the axial direction and a circumferential direction with regard to the axis; and   a length in the axial direction of a bond side passage of the plurality of cooling passages that is nearest to the bonded portion in the circumferential direction is shorter than a length in the axial direction of an adjacent passage of the plurality of cooling passages that is adjacent to the bond side passage in the circumferential direction.   
     
     
         37 . The transition piece according to  claim 35 , wherein a cross-sectional area of the bond side passage is larger than a cross-sectional area of the adjacent passage. 
     
     
         38 . The transition piece according to  claim 21 , wherein, in at least some cooling passages of the plurality of cooling passages, an inlet into which the cooling medium flows is formed at a downstream side end portion, and an outlet out of which the cooling medium flows is formed at an upstream side end portion. 
     
     
         39 . The transition piece according to  claim 21 , wherein the plurality of cooling passages each have the same cross-sectional area at any position in the axial direction. 
     
     
         40 . A combustor, comprising:
 the transition piece according to  claim 21 ; and   a fuel supply unit supplying fuel and air into the combustion gas flow path.   
     
     
         41 . A gas turbine, comprising:
 the combustor according to  claim 40 ;   a compressor that compresses air and supplies the compressed air to the combustor; and   a turbine that is driven by the combustion gas from the combustor.